Oligomerization reactions convert one or more reactants (e.g., ethylene) to one or more products (e.g., 1-hexene). The reactions generally take place in an oligomerization reactor, where the reactant(s) are fed. Reactants generally can react with other components (e.g., other reactants and/or catalyst) upon contact in the reactor. Undesirable byproducts such as polymer can be formed, and in some cases, the byproducts can accumulate as solids which foul part(s) of the reactor. There is an ongoing need to address fouling of oligomerization reactors.